Pretty difficult to test drive any of these with salt coated roads.
That does make it hard.
I've owned 3 C6s - 06, 08, 13; so let me put in my 2-cents.
First, get the newest one you can afford. Each year, they got better. Now for my personal experience.
The 06 was a coupe and my first auto Vette. I didn't like the paddle shift mode. The early 6-sp auto with paddle shifters was slow to up or down shift. Later versions were updated to provide better response.
However, if you never use the paddles, it really doesn't matter. My wife and I both preferred the Sport mode when driving and we stopped using the paddles. My wife drove it as a daily driver and it performed very well.
The 08 was a vert manual. I had problems with this car. First, the clutch pedal stuck to the floor once - new clutch, new master and slave cylinders and new fluid and it was fine until traded. Second, I think it was struck by lightning or got hit by a electromagnetic pulse related to the storm I was in. Whatever, that fried 3 of the computers in the car. Since the diagnostics wouldn't work, it took the dealer 10 weeks to track down all the problems. After that was fixed, it again performed very well.
The 13 is a 427 Vert, manual. I love this car! But, I don't think you are looking for this sort of Vette.
Good luck with your search.